JP4826711B2 - Needle - Google Patents

Description

  The present invention relates to a medical injection needle, and more particularly to an injection needle suitable for drug injection into an internal hemorrhoid tissue.

  Hemorrhoids are a type of hemorrhoid caused by blood circulation disorders (congestion) in the anus. This hemorrhoid is divided into an inner hemorrhoid that occurs above the tooth line of the anus and an outer hemorrhoid that occurs at the lower part, and the inner hemorrhoid accounts for 40-60% of the total.

  In the present treatment of internal hemorrhoids, conservative therapy such as drug treatment is performed in cases of mild to moderate disease, and radical treatment by surgery is performed in the case of becoming severe. However, in the case of surgery, since there is anxiety about postoperative pain and bleeding, and hospitalization is required for about 10 days, there are many patients who suffer without going to the hospital.

  In order to solve this problem, the following drug treatment is proposed instead of surgery even in the case of severe internal hemorrhoids. In this treatment, a drug (medical solution) is directly injected into a soft internal hemorrhoid tissue to cure the internal hemorrhoid tissue. By the way, in the above treatment, there is a concern that serious side effects may occur when the drug is erroneously injected not into the internal hemorrhoid tissue but into the hard rectal muscle layer under the internal hemorrhoid tissue.

  Therefore, during the above treatment, when the needle is punctured (pierced) into the internal hemorrhoid tissue (affected area layer), the puncture resistance is low, and the needle is erroneously punctured into the rectal muscle layer under the internal hemorrhoid tissue. In such a case, an injection needle whose piercing resistance is large, that is, an injection needle capable of discriminating the internal hemorrhoidal tissue from the rectal muscle layer is required. However, in the past, the actual situation is that there was no injection needle as described above.

  The problem to be solved was that when a drug was injected into the internal hemorrhoid tissue, there was no injection needle that could distinguish the internal hemorrhoid tissue and the rectal muscle layer under the tissue due to the difference in piercing resistance. It is.

An object of the present invention is to provide an injection needle that can solve the above problems, and in order to achieve the object, the present invention is characterized in that it is used for injection of a drug into the internal hemorrhoid tissue. The tip of the needle tube is polished obliquely with respect to its axis, the polished surface is used as the blade surface, and the blade surface is provided on the first inclined surface on the base side and on both sides on the tip side. The second inclination angle that is an angle formed between the second inclined surface and the axial center is larger than the first inclination angle that is an angle formed between the first inclined surface and the axial center. In the injection needle, the formation angle which is an angle formed by both the second inclined surfaces is 50 ° to 90 °.
The first inclination angle may be 8 to 20 °.
Further, the second inclination angle may be set to 21 ° to 31 °.
Furthermore, the blade surface length L1, which is the length of the blade surface in the axial direction, may be 1.0 to 5.0 mm.
Further, when the length of the second inclined surface in the axial direction is set to the side cut length L2, the side cut ratio L2 / L1 may be set to 0.25 to 0.65.

  According to the present invention, when the injection needle is punctured (pierced) into the internal hemorrhoid tissue, the piercing resistance is low, and when the injection needle is erroneously inserted into the rectal muscle layer under the internal hemorrhoid tissue, the puncture is performed. Since the through resistance is increased, the drug (medicine solution) can be reliably injected into the internal hemorrhoid tissue, and the drug can be prevented from being erroneously injected into an inappropriate site such as the rectal muscle layer under the internal hemorrhoid tissue.

  The present invention provides an injection needle capable of discriminating an internal hemorrhoid tissue and a rectal muscle layer under the tissue by a difference in piercing resistance when a drug (medical solution) is injected into the internal hemorrhoid tissue.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the following description, for the sake of convenience, the left of FIG. 1 will be described as the front, the top and bottom of FIG. 1 will be the left and right, and the top of FIG. The injection needle of the present invention is formed as follows. That is, the tip portion of the straight tubular needle tube 1 is polished (ground) obliquely with respect to the axis C thereof, and a sharpened sharpened portion 2 is formed toward the front, and the portion excluding the sharpened portion 2 of the needle tube 1 Is the main body 3. The upper surface of the sharpened portion 2, that is, the obliquely polished surface is the blade surface 4, and the tip is the blade edge 5. The blade surface 4 has a first inclined surface (first bevel) 6 on the base side and a pair of second inclined surfaces (second bevel) 7 on both the left and right sides on the distal end side. The second inclined surface 7 is formed in a continuous (continuous) shape with respect to the first inclined surface 6, and both the second inclined surfaces 7 are formed in a parallel (continuous) shape in the left-right direction.

  As the needle tube 1, the same one as the conventional one is used. As shown in Table 1, for example, the length L is 13 to 70 mm, and the value used frequently (high frequency value) is: 44 mm, outer diameter O.D. D. Is 0.3 to 1.25 mm, a frequently used value (high frequency value) is 0.51 mm, its inner diameter I.V. D. Is 0.16 to 1.04 mm, and a frequently used value (high frequency value) is 0.29 mm. The material of the needle tube 1 includes steel materials including stainless steel, non-ferrous metal materials such as aluminum, copper and titanium, heat resistant materials such as nickel, cobalt and molybdenum, low melting point metals such as lead and tin, gold, silver, Precious metal materials such as platinum and their alloys are used. As the needle tube 1, not only a straight tube but also a cylindrical body having a tapered shape toward the distal end or the proximal end, or a cylindrical body having a tapered shape from a midway portion in the axial center direction of the blade surface 4 may be used. .

  The injection needle is manufactured in the conventional manner as follows. That is, the needle tube 1 is cut to a predetermined length so that the needle tube 1 is not bent, clogged, or has an overall abnormality, and the burr on the cut surface on the needle base side is removed. Next, the first and second inclined surfaces 6 and 7 of the blade surface 4 are formed by polishing as follows. At the time of this polishing process, the needle tube 1 is polished at an appropriate polishing rate and the first and second inclined surfaces 6 and 7 of the blade surface 4 are balanced so that the needle tube 1 is not damaged by the heat at the time of polishing and it is difficult to generate burrs. Formed in a well-shaped shape.

  First, as a first stage of polishing, a disk (column) -shaped rotating grindstone is disposed above the tip of the needle tube 1, and FIG. 6 (in FIG. 6, the axis D of the rotating grindstone is used for convenience of explanation. And the distance between the needle tube 1 and the needle tube 1 is smaller than the actual distance.) In plan view, the rotational axis D of the rotating grindstone is perpendicular to the axis C of the needle tube 1 and then the outer periphery of the rotating grindstone. The tip of the needle tube 1 is polished with a surface to first roughly form the blade surface 4. Next, as the second stage of polishing, the tip of the blade surface 4 is further polished with a rotating grindstone. At this time, the rotating grindstone is moved left and right from the polishing position around the axis C of the needle tube 1. The outer peripheral surface of the rotating grindstone is rotated relative to each other (actually, the needle tube 1 is rotated in each circumferential direction without rotating the rotating grindstone. The same applies hereinafter). Thus, the left and right sides of the tip of the blade surface 4 are polished. Thus, the portion of the blade surface 4 that has not been polished in the second stage becomes the first inclined surface 6, and the portion polished in the second stage becomes the second inclined surface 7.

  When removing burrs generated during polishing, after covering the blade edge 5 so that the blade edge 5 is not damaged, the outer diameter is several tens of μm on the entire first inclined surface 6 and the base side of the second inclined surface 7. Spray glass beads (blasting) to remove burrs. The burrs on the blade edge 5 are removed by electropolishing so that the ridge line appears clearly. Thereafter, the needle tube 1 is subjected to a rust prevention treatment with an acid, and then subjected to a cleaning treatment.

  By the way, in the injection needle, the length L1 of the blade surface 4 in the axial direction is the blade surface length, and the blade surface length L1 is 1.0 to 5.0 mm, preferably 1.7 ± 0.4 mm. It is said.

  The first inclined surface 6 is parallel to the radial direction of the left and right direction (horizontal direction) of the needle tube, and is flat or substantially flat as a whole. The angle formed between the first inclined surface 6 and the axis C is a first inclination angle (first bevel angle) α, and the first inclination angle α is 8 to 20 °, preferably 13 ± 2 °. The

  As shown in FIG. 5, the second inclined surfaces 7 on the left and right sides are axisymmetric and have the same shape when viewed from the axial direction, and the first inclined surface 6 and the second inclined surfaces 6 are the same. A ridge line 9 is formed at the boundary of the inclined surface 7. The ridge line 9 is inclined with respect to the radial direction so as to be higher as it goes outward in the radial direction. The length of the second inclined surface 7 in the axial center direction is set as a chamfering length L2, and a chamfering ratio L2 / L1 is set to 0.25 to 0.65, preferably 0.45 ± 0.2. Is done.

  The injection needle is rotated in each direction in the circumferential direction from the state shown in FIG. 2, and as shown in FIGS. 3 and 4, when viewed from the side, the second inclined surface 7 on one of the left and right sides appears to be linear. At this time, an angle formed between the second inclined surface 7 and the axis C is set to a second inclination angle (second bevel angle) β. The second inclination angles β on the left and right sides are the same and are 21 ° to 31 °, preferably 26 ± 2 °.

  As shown in FIG. 6, when the second inclined surface 7 is viewed from the axial direction with the blade surface 4 on the upper side, each second inclined surface 7 becomes lower as it goes radially outward. It is also inclined in the radial direction so that The inclination of the second inclined surface 7 and the ridgeline 9 in the radial direction is determined by the diameter of the rotating grindstone and the angle (rotation angle) by which the rotating grindstone is rotated left and right during polishing. The formation angle θ, which is an angle formed by both the second inclined surfaces 7, is 50 to 90 °, and preferably 70 ± 10 °. In this case, the rotation angle is 90 ° to 130 ° (45 ° to 65 ° on the left and right), preferably 110 ± 10 ° (55 ± 10 ° on the left and right).

  According to the embodiment configured as described above, when treating severe internal hemorrhoids with a medicine (medicine solution), the syringe needle of the present invention is connected to a syringe (not shown), and the medicine is placed in the syringe. After aspiration, the needle is punctured (pierced) into the inner hemorrhoid.

  At this time, the formation angle θ of the second inclined surfaces 7 at the distal end of the sharpened portion 2 of the injection needle is set to 50 to 90 °, which is smaller than the conventional 110 °. Since the cross-sectional area on the distal end side is smaller than that of the prior art and the inner hemorrhoid itself is soft, the injection needle can be easily punctured (pierced) into the inner hemorrhoid with a small puncture resistance.

  If the piercing resistance is too small, it may be difficult to clearly tell the practitioner that the injection needle has been pierced into the inner hemorrhoid, so the second inclination angle β of the second inclined surface 7 is 21 ° to 31. As a result, the piercing resistance is increased. In some cases, the second inclination angle β of the second inclined surface 7 is set to a value smaller than the above, and the piercing resistance is not increased.

  By the way, when the injection needle is punctured into the inner hemorrhoid and not only the distal end portion of the sharpened portion 2 of the injection needle but also the base portion thereof is inserted into the tissue of the inner hemorrhoid, the cross-sectional area of the inserted portion is increased. Since it gradually increases, the piercing resistance of the injection needle also gradually increases.

  At this time, if the injection needle is inserted too much, first, as the first step, the tip of the sharpened portion 2 of the injection needle is inserted into the rectal muscle layer under the internal hemorrhoid tissue, and as the second step, the sharpened portion of the injection needle is inserted. The base of part 2 will be inserted into the rectal muscle layer under the internal hemorrhoidal tissue.

  In the first stage, the formation angle θ of both the second inclined surfaces 7 is 50 to 90 °, and the cross-sectional area of the tip portion pierced into the rectal muscle layer at the sharpened portion 2 is smaller than before. The piercing resistance due to the angle formed by the second inclined surfaces 7 is small. However, the second inclination angle β of the second inclined surface 7 is set to be as large as 21 ° to 31 °, the piercing resistance due to the second inclination angle β is large, and the rectal muscle layer itself is hard. In some cases, the piercing resistance of the injection needle increases.

  In the second stage, since the first inclination angle α of the first inclined surface 6 is 8 to 20 °, which is smaller than the second inclination angle β of the second inclined surface 7, the piercing caused by the second inclination angle is performed. Resistance is small. However, in the first stage, the formation angle θ of both the second inclined surfaces 7 is 50 to 90 °, and due to this, the cross-sectional area of the tip portion pierced into the rectal muscle layer at the sharpened portion 2 Is smaller than before. On the other hand, in the second stage, the first inclined surface 6 is parallel to the radial direction of the needle tube 1 in the left-right direction (horizontal direction), and the first inclined surface 6 is the second inclined surface 7, that is, the first stage. Bulges to the upper side and the left and right sides (radially outward), and as a result, the cross-sectional area of the portion to be punctured into the rectal muscle layer in the sharpened portion 2 is sharper than in the first stage. Increase. Thereby, the rectal muscle layer itself may be hard, and the piercing resistance of the injection needle increases at a stroke.

  Although the puncture of the rectal muscle layer of the injection needle has been described in two stages as described above, since the chamfer length L2 of the second inclined surface 7 is small, in actual injection, the first The second stage occurs substantially simultaneously, which dramatically increases the penetration resistance when the injection needle is punctured into the rectal muscle layer under the internal hemorrhoidal tissue.

  As described above, after the needle is reliably punctured into the internal hemorrhoid tissue, the drug is injected into the internal hemorrhoid tissue.

  As mentioned above, when the needle is punctured into the internal hemorrhoid tissue, its puncture resistance is low, and when the needle is accidentally punctured into the rectal muscle layer under the internal hemorrhoid tissue, the puncture resistance is large. Therefore, the drug can be reliably injected into the internal hemorrhoid tissue, and the drug can be prevented from being erroneously injected into an inappropriate site such as the rectal muscle layer under the internal hemorrhoid tissue.

[Test Example 1 and Comparative Example 1]
Next, the present invention will be further described with reference to Test Example 1 in which the present invention was implemented and Comparative Example 1. However, the present invention is not limited to the test examples.

  O.D. D. Is 0.51 mm, the wall thickness is 0.10 mm, the blade surface length L1 is 1.7 mm, the first inclination angle α is 13 °, the second inclination angle β is 26 °, and the formation angle θ of both second inclination surfaces is 70. Five injection needles with an angle of 0 were produced and designated as Test Example 1. Also, the outer diameter O.D. D. And the wall thickness L1 is the same as described above, the blade face length L1 is 2.4 mm, the first inclination angle α is 10 °, the second inclination angle β is 18 °, and the formation angle θ of both the second inclination surfaces is 110 °. Five injection needles were produced and used as Comparative Example 1.

  The hemorrhoid model shown in FIG. 7 was used for the test. This hemorrhoid model is a disc (column) made of silicone rubber, and includes an upper disc 11 that imitates the inner hemorrhoid tissue, a lower disc 12 that imitates the rectal muscle layer under the inner hemorrhoid tissue, and these upper and lower discs. 11 and 12 has a ring-shaped frame 13 into which the 12 and 12 are inserted. The upper surface of the upper disk 11 is a flat surface. On this upper surface, raised portions 14 protruding upward are formed at intervals in the circumferential direction. The reason for forming the raised portion 14 is to adjust the length of the piercing portion of the injection needle.

  From above the upper and lower disks 11 and 12 of the inner hemorrhoid model, the injection needles of Test Example 1 were pierced vertically at a piercing speed of 20 mm / min, and the piercing resistance was measured using a universal testing machine (instrument Ron, Inc .: Model No. 5565), and the measurement results are averaged, and as shown by the solid line in FIG. 8, the relationship between the insertion amount (mm) and the penetration resistance (N) with respect to the hemorrhoid model of the injection needle is shown. A graph was obtained. Each of the injection needles of Comparative Example 1 was measured in the same manner as described above, and a graph showing the relationship between the insertion amount (mm) of the injection needle with respect to the hemorrhoid model and the penetration resistance (N) was obtained as shown by the dotted line in FIG. It was.

  In the hemorrhoid model, when the insertion amount of the injection needle into the hemorrhoid model is smaller than the straight line A in FIG. 8, that is, the straight line A, and the injection needle is punctured only in the upper disk 11. Is considered that the injection needle is pierced into the internal hemorrhoid tissue, the insertion amount of the injection needle into the hemorrhoid model is larger than the straight line A, that is, the injection needle is inserted into the upper disc. When not only 11 but also the lower disc 12 is punctured, it is considered that the injection needle is pierced into the rectal muscle layer.

  Referring to FIG. 8, when the injection needle is punctured into the rectal muscle layer, the puncture resistance in Test Example 1 increases more rapidly than in Comparative Example 1. Therefore, by using the injection needle of the present invention, it is possible to prevent the drug from being erroneously injected into an inappropriate site such as the rectal muscle layer under the internal hemorrhoid tissue.

It is a top view which shows one embodiment of this invention. It is a side view of FIG. It is the side view which rotated the injection needle of FIG. 2 around the shaft center. It is the side view which rotated the injection needle of FIG. 2 around the shaft center. It is a front view of FIG. FIG. 3 is a cross-sectional view taken along line AA in FIG. 2. It is a longitudinal cross-sectional view of an inner hemorrhoid model. It is a graph which shows a test result.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Needle tube 2 Sharp part 4 Blade surface 6,7 1st, 2nd inclined surface C Axis center L1 Blade surface length L2 Side-cutting length α, β 1st, 2nd inclined angle θ Formation angle

Claims (5)

Used to inject drugs into the internal hemorrhoid tissue,
The tip of the needle tube is polished obliquely with respect to its axis, and the polished surface is used as the blade surface.
The blade surface has a first inclined surface on the base side and a pair of second inclined surfaces on both sides on the distal end side, and the second inclined angle, which is an angle formed by the second inclined surface and the axis, In the injection needle that is made larger than the first inclination angle that is an angle formed by one inclined surface and the axis,
An injection needle having a formation angle of 50 ° to 90 °, which is an angle formed by both second inclined surfaces.   The injection needle according to claim 1, wherein the first inclination angle is 8 to 20 °.   The injection needle according to claim 1 or 2, wherein the second inclination angle is 21 ° to 31 °.   The injection needle according to any one of claims 1 to 3, wherein a blade surface length L1 which is a length of the blade surface in the axial direction is 1.0 to 5.0 mm.   The injection needle according to claim 4, wherein when the length of the second inclined surface in the axial direction is set to the side cut length L2, the side cut ratio L2 / L1 is set to 0.25 to 0.65.

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